Facebook CEO Mark Zuckerberg just delivered what amounts to a massive cultural change for the social network. Soon, users will be able to utilize an anonymous login function. It will let people use Facebook to log in to websites and apps, but without telling those apps — or their Facebook friends — what they're doing.

Zuck used to argue that if you were trying to do something anonymously on the Web it meant there was something wrong with you. He once famously said, “Having two identities for yourself is an example of a lack of integrity.”

No longer.

Anonymous Facebook login solves one of the big complaints about Facebook: People use their Facebook ID to use Spotify or Pandora or Rdio, and all of a sudden, "Jane Doe is listening to Britney Spears right now," appears in your news feed. It's embarrassing.

So Zuckerberg has delivered a solution to the app-login ambush, in which users are surprised that they're sharing stuff with the world simply because they wanted to try out an app only briefly.

Anonymous login could drive a whole new way to try, download and sample apps (without telling your friends you're back on Tinder or Grindr, again).

It sounds kinda technical, but for the app developer community, any new way to encourage people to download new apps is a huge welcome step. Zuck was actually cheered off the stage by the roughly 2,000 programming and development nerds who came to see him speak — just for delivering this one improvement.

The Facebook F8 conference for software and app developers is being held in a trendy media space on San Francisco's 8th Street, called the Concourse. Basically, it's a massive barn-like warehouse that Facebook has filled with info booths at which you can ask staff about every aspect of its business.

Zuckerberg used the conference to make the case that if you are building, distributing or marketing a new app then Facebook has got all the tools you need.